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    <title>Bracket tests</title>
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    <h2>Bracket tests</h2>

    <h3>Classical vertical bracket test</h3>

        <p>
            Classical vertical bracket test is shown on picture 1.It can measure vertical associated phoria and vertical aniseikonia.
        </p>

        <p>
            During examination patient can independently:
            <ul>
                <li>move right bracket up (key &uarr;) or down (key &darr;)</li>
                <li>extend (key &rarr;) or shorten (key &larr;) right bracket.</li>
            </ul>
        </p>

        <p>
            Examination results are announce as two numbers separated by slash.
            First number expressed in minutes af angle concerns vertical assoctiated phoria.
            Second number expressed in procent concerns vertical aniseikonia.
        </p>
        <p>
            Phoria &alpha; is calculated from following equation
            on the basics of right brakect movement <i>x</i> and distance from monitor <i>l</i>.
            <center>
                <img src="../../images/eqnPhoria.png" />
            </center>
        </p>
        <p>
            Aniseikonia <i>A</i> is calculated from following equation 
            on the basics of initial right bracket size <i>x</i>, final right bracket size <i>y</i> and distance from monitor <i>l</i>.
            <center>
                <img src="../../images/eqnAniseikonia.png" />
            </center>
        </p>


    <br><br>
    <h3>Vertical bracket test without central stimulus</h3>

        <p>
            Vertical bracket test without central stimulus is shown on picture 2.
            It's independent modification of classical vertical bracket test, so there are no data about result interpretation.
        </p>
        <p>
            During examination patient can independently move and resize right bracket as previous.
        </p>
        <p>
            Result is calculated and presented as previous.
        </p>



    <br><br>
    <h3>Classical horizontal bracket test</h3>
        <p>
            Classical horizontal bracket test is shown on picture 3.
            It can measure horizontal associated phoria and horizontal aniseikonia.
        </p>

        <p>
            During examination patient can independently:
            <ul>
                <li>move lower bracket left (key &larr;) or right (key &rarr;),</li>
                <li>extend (key &uarr;) or shorten (key &darr;) lower bracket.</li>
            </ul>
        </p>

        <p>
            Examination results are announce as two numbers separated by slash.
            First number expressed in munutes af angle concerns horizontal assoctiated phoria.
            Second number expressed in procent concerns horizontal aniseikonia.
        </p>
        <p>
            Phoria &alpha; is calculated from following equation
            on the basics of lower brakect movement <i>x</i> and distance from monitor <i>l</i>.
            <center>
                <img src="../../images/eqnPhoria.png" />
            </center>
        </p>
        <p>
            Aniseikonia <i>A</i> is calculated from following equation
            on the basics of initial lower bracket size <i>x</i>, final lower bracket size <i>y</i> and distance from monitor <i>l</i>.
            <center>
                <img src="../../images/eqnAniseikonia.png" />
            </center>
        </p>


    <br><br>
    <h3>Horizontal bracket test without central stimulus</h3>
        <p>
            Horizontal bracket test without central stimulus is shown on picture 2.
            It's independent modification of classical horizontal bracket test, so there are no data about result interpretation.
        </p>
        <p>
            During examination patient can independently move and resize lower bracket as previous.
        </p>
        <p>
            Result is calculated and presented as previous.
        </p>


        <br><br><br>
        <center>
            <img src="../../images/testBracketVertical.png" />
            <br/>
            <i>Image 1. Classical vertical bracket test</i>
        </center>
        <br><br><br>
        <center>
            <img src="../../images/testBracketVerticalWithoutCircle.png" />
            <br/>
            <i>Image 2. Vertical bracket test without central stimulus</i>
        </center>
        <br><br><br>
        <center>
            <img src="../../images/testBracketHorizontal.png" />
            <br/>
            <i>Image 3. Classical horizontal bracket test</i>
        </center>
        <br><br><br>
        <center>
            <img src="../../images/testBracketHorizontalWithoutCircle.png" />
            <br/>
            <i>Image 4. Horizontal bracket test without central stimulus</i>
        </center>
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